<template>
  <div>
  <div class="goods">
    <div class="menu-wrapper" ref="left">
      <ul ref="leftUl">
        <li class="menu-item" v-for="(good,index) in goods" :key="good.name" :class="{current:index==currentIndex}"
        @click="clickItem(index)">
          <span class="text bottom-border-1px">
            <img class="icon" :src="good.icon" v-if="good.icon">
         {{good.name}}</span>
        </li>
      </ul>
    </div>
    <div class="foods-wrapper" ref="right">
      <ul ref="rightUl">
        <li class="food-list-hook" v-for="(good,index) in goods" :key="index" >
          <h1 class="title">{{good.name}}</h1>
          <ul>
            <li class="food-item bottom-border-1px" v-for="(food,index) in good.foods" :key="index" @click="showFood(food)">
              <div class="icon">
                <img width="57" height="57"
                     :src="food.icon">
              </div>
              <div class="content">
                <h2 class="name">{{food.name}}</h2>
                <p class="desc">{{food.description}}</p>
                <div class="extra">
                  <span class="count">月售{{food.sellCount}}份</span>
                  <span>好评率{{food.rating}}%</span></div>
                <div class="price">
                  <span class="now">￥{{food.price}}</span>
                   <span class="old" v-if="food.oldPrice">￥{{food.oldPrice}}</span>
                </div>
                <div class="cartcontrol-wrapper">
                <cart-control :food="food"/>
                </div>
              </div>
            </li>
          </ul>
        </li>
      </ul>
    </div>
    <ShopCart/>
  </div>
  <Food :food="food" ref="food"></Food>
</div>
</template>

<script>
import BScroll from 'better-scroll'
import {mapState} from 'vuex'
import CartControl from '../../../components/CartControl/CartControl.vue'
import Food from '../../../components/Food/Food.vue'
import ShopCart from '../../../components/ShopCart/ShopCart'

  export default {
  components: { CartControl ,Food,ShopCart},
    name:'ShopGoods',
    data(){
      return{
        scrollY:0,
        tops:[],
        food:{}
      }
    },
    methods:{
      showFood(food){
        this.food=food
        this.$refs.food.toggleShow()
      },
      _initScroll(){
        if(!this.leftScroll){
           this.leftScroll=new BScroll(this.$refs.left,{
          click:true
        })
         this.rightScroll=new BScroll(this.$refs.right,{
          probeType:1,
            click:true
        })
        this.rightScroll.on("scroll",({x,y})=>{
          this.scrollY=Math.abs(y)
        })
        this.rightScroll.on("scrollEnd",({x,y})=>{
          this.scrollY=Math.abs(y)
        })
        }else{
          this.leftScroll.refresh()
          this.rightScroll.refresh() 
        }
       

      },
      _initTops(){
        const tops=[]
        let top=0
        tops.push(top)
        const lis=Array.prototype.slice.call(this.$refs.rightUl.children)
        lis.forEach((li)=>{
          top+=li.clientHeight;
          tops.push(top)
        })
        this.tops=tops
      },
      clickItem(index){
        const top=this.tops[index]
        this.scrollY=top
        this.rightScroll.scrollTo(0,-top,300)
      }
    },
      computed:{
        ...mapState({
          goods:state=>state.shop.shop.goods|| []
        }),
        currentIndex(){
          const {scrollY,tops}=this
         const index=tops.findIndex((top,index)=>scrollY>=top && scrollY<tops[index+1])
         if(index!==this.index&&this.leftScroll){
           this.index=index;
           const li=this.$refs.leftUl.children[index]
           this.leftScroll.scrollToElement(li,300)
         }
         return index
        }

      },
      mounted(){
        if(this.goods.length>0){
          this._initScroll()
         this._initTops()
        }
      },
      watch:{
        goods(){
         this.$nextTick(()=>{
         this._initScroll()
         this._initTops()
          })
        }
      }
  }
</script>
<style lang="stylus" rel="stylesheet/stylus" scoped>
  @import "../../../assets/stylus/mixins.styl"
  .goods
    display: flex
    position: absolute
    top: 225px
    bottom: 46px
    width: 100%
    background: #fff;
    overflow: hidden
    .menu-wrapper
      flex: 0 0 80px
      width: 80px
      background: #f3f5f7
      .menu-item
        display: table
        height: 54px
        width: 56px
        padding: 0 12px
        line-height: 14px
        &.current
          position: relative
          z-index: 10
          margin-top: -1px
          background: #fff
          color: $green
          font-weight: 700
          .text
            border-none()
        .icon
          display: inline-block
          vertical-align: top
          width: 12px
          height: 12px
          margin-right: 2px
          background-size: 12px 12px
          background-repeat: no-repeat
        .text
          display: table-cell
          width: 56px
          vertical-align: middle
          bottom-border-1px(rgba(7, 17, 27, 0.1))
          font-size: 12px
    .foods-wrapper
      flex: 1
      .title
        padding-left: 14px
        height: 26px
        line-height: 26px
        border-left: 2px solid #d9dde1
        font-size: 12px
        color: rgb(147, 153, 159)
        background: #f3f5f7
      .food-item
        display: flex
        margin: 18px
        padding-bottom: 18px
        bottom-border-1px(rgba(7, 17, 27, 0.1))
        &:last-child
          border-none()
          margin-bottom: 0
        .icon
          flex: 0 0 57px
          margin-right: 10px
        .content
          flex: 1
          .name
            margin: 2px 0 8px 0
            height: 14px
            line-height: 14px
            font-size: 14px
            color: rgb(7, 17, 27)
          .desc, .extra
            line-height: 10px
            font-size: 10px
            color: rgb(147, 153, 159)
          .desc
            line-height: 12px
            margin-bottom: 8px
          .extra
            .count
              margin-right: 12px
          .price
            font-weight: 700
            line-height: 24px
            .now
              margin-right: 8px
              font-size: 14px
              color: rgb(240, 20, 20)
            .old
              text-decoration: line-through
              font-size: 10px
              color: rgb(147, 153, 159)
          .cartcontrol-wrapper
            position: absolute
            right: 0
            bottom: 12px
</style>